الفهرس 
Abstract
Lithostratigraphy.Only 14 pages are availabe for public view
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Abstract
Two active oil seeps are found in the southern Gulf of Suez rift at Gebel El Zeit and Gemsa areas. The presence of oil at the area had been known for thousands of years. Oil discharges were observed at Gemsa area during the last five years following the recording of earthquake events. Oil seeps affect the coastal habitat and marine life due to their toxicity. Nature and origin of these oil seeps are the main aims of the present study.
At the study area, detailed stratigraphic setting, surface geological mapping followed by subsurface mapping using integration of aeromagnetic data, 2-D seismic lines and well log data are accomplished in order to produce a coherent interpretation of the main causes of the oil seepage. The seismic and borehole data of the Gemsa area are very old and poor, which makes geologic modeling of the area a challenging task.
Neotectonics is assured in the study area using uplifted coral terraces, earthquake data, and borehole breakout data. The concerned site was subjected to numerous earthquakes with magnitudes ranging from 1 to 6 Mb. The seismic activity is conformable in time and related to active major faults and structural lineaments.
An increase in fluid expulsion during the activation of normal faults has been suggested in the present study although the activation took place along a distant fault. Ground motion resulted from earthquakes could increase permeability through faults and associated pre-existing or new formed fractures because of changes in fracture aperture, and that give opportunity for oil to migrate to reach its surface location. Because the dynamic shear strain caused by distant earthquakes is small, increase in permeability might be related to reopening of a network of existing fractures, rather than creation of new fractures.
The produced migration pathway maps suggest the possibility of new unexplored blocks of Nubia Sandstone and Hammam Faraun Member at Ras El Ush and Gemsa oilfields, respectively. The original oil in place of the predicted reservoir of Ras El Ush block is estimated to be around 47.5 MMBO while it is estimated to be around 22 MMBO for Gemsa block, which support the design makers for more investigation to increase its certainty.